产品简介/Product introduction
井盖状态+水位超限智能监测终端包含井盖异动和水位超限两部分，主要用来监测井盖状态是否正常及排水井中水位状态是否正常。安装在井盖下面，井盖以水平放置且水位正常可视为正常状态。当井盖发生倾斜并达到触发报警条件（例如：倾斜角大于10°（倾角可设定））或排水井中水位超限时，将会触发报警信号并通过无线传输方式发送至监控中心，监控中心对数据进行解析并判断警情。
该终端产品可提供LoRaWAN、NBIOT、GPRS三种无线通讯方式。终端外形见图1，其使用电池供电，具有安装方便、电池寿命长、检测准确率高，工作稳定等特点。
The intelligent monitoring terminal of well cover status + water level overrun includes two parts: the well cover transfer and the water level overrun, which is mainly used to monitor whether the state of the well cover is normal and whether the state of the water level in the drainage well is normal. Installed under the manhole cover, the manhole cover is placed horizontally and the water level is normal. When the well cover tilts and reaches the trigger alarm condition (for example, the inclination Angle is greater than 10° (the inclination Angle can be set)) or the water level in the drainage well exceeds the limit, the alarm signal will be triggered and sent to the monitoring center through wireless transmission, the monitoring center analyzes the data and judges the alarm.
The terminal product can provide LoRaWAN, NBIOT, GPRS three wireless communication modes. The terminal shape is shown in Figure 1. It uses battery power supply and has the characteristics of easy installation, long battery life, high detection accuracy and stable operation.
工作原理/Working principle
井盖状态+水位超限监测终端安装在井盖背面，终端通过加速度传感器测量井盖当前的倾斜角度，通过水位浮球检测水位是否超限。当该倾角值大于设定的报警值或浮球向上浮起时触发报警（当倾角大于90°时，无条件报警），并通过无线网络将报警信息发送至监控中心。
终端支持设置定时上报时间间隔和报警角度阈值。非报警状态下，终端以定时上报时间间隔发送上报报文。在报警状态下，终端以立即发送上报报文，当角度和水位恢复正常时，终端也会立即发送报文到平台。报文中的设备状态位用来指示当前的报警状态。设备状态位还可以指示当前的电量状态以及其他状态。
井盖异动的检测条件是：|井盖当前角度值 – 井盖背景角度值| ＞ 报警角度阈值。该条件满足时，发送报警信息。当倾角大于90°时，无条件报警。
水位超限的检测条件是：水位上升，浮球竖直向上浮起，如下水位上升示意图所示，即为报警状态。
The monitoring terminal of manhole cover status + water level overrun is installed on the back of the manhole cover. The terminal measures the current inclination Angle of the manhole cover through the acceleration sensor, and detects whether the water level is overrun through the water level float. When the inclination value is greater than the set alarm value or when the float floats upward, the alarm is triggered (when the inclination is greater than 90°, unconditional alarm), and the alarm information is sent to the monitoring center through the wireless network.
The terminal supports setting the periodic reporting interval and alarm Angle threshold. In the non-alarm state, the terminal sends the reported packets at a periodic reporting interval. In the alarm state, the terminal immediately sends the report message, when the Angle and water level return to normal, the terminal will immediately send the message to the platform. The device status bits in the message indicate the current alarm status. The device status bit can also indicate the current battery status and other states.
The detection conditions of manhole cover transaction are: | current Angle value of manhole cover - background Angle value of manhole cover | > alarm Angle threshold. When this condition is met, alarm information is sent. When the Angle is greater than 90°, unconditional alarm.
The detection condition of the water level exceeding the limit is as follows: the water level rises and the float floats vertically upward, as shown in the following diagram of the water level rise, that is, the alarm state.
